Railway-carriage ventilator.



F. H. ADDIS.

RAILWAY CARRIAGE VENTILATOR.

APPLIOATION FILED JAN. 9, 1914.

1 1;; Patented Feb. 23, 1915.

Jimmy THE NORRIS PETERS C0,, PHOTO-LITHO.. WASHINGTON, D" C,

FREDERICK HENRY ADDIS, OF .AJ'ME R, INDIA.

RAILWAY-CARRIAGE VENTILATOR.

Specification of Letters Patent.

Application filed January 9, 1914. Serial No. 811,237.

To all whom it may concern:

Be it known that I, FREDERICK HENRY Annie, a subject of the Emperor ofIndia, residing at Ajmer, India, have invented a new and useful ImprovedRailway-Carriage Ventilator, of which the. following isa specificaticn.

My invention relates to an improved air extractor or exhaust ventilatorof the type in which the motion of the outer atmosphere acts as a mctiveforce inducing a current of foul air from the interior of the space towhich the ventilator is attached toward the outside.

My apparatus is especially designed for the roofs of railway cars,tramcars and the like.

In modern railway carriage design, especially of carriages for hot cars,it is found desirable to increase the air space in the in terior of thecar by raising the roof as near as possible to the maximum loading gageallowable. This close approach to the maximum height however involvesthe drawback that it is impossible to use ordinary ventilatorsprojecting considerably above the level of the car roof. But ventilatorswhich dovnct exhaust the air from the top of the carriage are of littleuse in such constructions. It is therefore necessary that the ventilatorshould not exceed the height of two or three inches at the outside abovethe level of the car roof. It is further necessary that the ventilatorshould be equally efficient in either direction of motion, also that nomoving parts, adjustable knobs or other mechanism requiring attention orlikely when worn to become noisy, should be required to give theventilating effect. Moreover, the air ducts and outletsmust give themaximum area possible under the circumstances without any angular bendstending to check the outflow of the air aspirated by the outer aircurrent, and this air current must be so deflected between the car roofand the outlet of the ventilator that it can only operate as anaspirating current and not under any conditions induce or become a downdraft through the ventilator.

My invention is distinguished from prior constructions of the type bythe combination of these essential features. Its height above the top ofthe car roof need not exceed two or three inches; the aspiration isoperative while the train is running in either direction and also whilethe train is vents. the

ders from the engine and the area of the exhaust is large, thuseffecting rapid renewal of the air.

The ventilator is illustrated in the accompanylng drawings in verticalsectional elevatlons.

A represents an annular plate resting upon the roof of the railway car,B the ventilator shaft passing through the car roof into the interiorthereof, C the annular curved suction funnel fixed upon the uptake B andD represents the central directing cone.

E E are bolts or stays holding the plates together. An annulus Fsurrounds the suction funnel C at about its junction with the uptake Band this annulus is directed downward from the center, so that its outerperiphery J is nearer the plate A or the car roof than its innerperiphery connected to Moreover, the closing annulus G which joins theoutlet of the suction funnel to the covering plate H of the ventilatoris inclined sharply downward at an angle of about 30 in like manner, sothat the outlet of the suction funnel is at the apex of the inclinationsof these two annuli. The plate H may be transparent or have a window H.

The material of which the ventilator is made is preferably sheet metalof suitable strength. Obviously, the ventilator may be made of any othersuitable material, if thought desirable.

The operation of the apparatus is as follows :-Let us assume that thewind strikes the ventilator in the direction indicated by the arrow K.The wind impinges upon the front surface of the annulus G and isdeflected downward and blows past the orifice of the annulus C producingan aspiration of the air upward through B. Even if rain, dust or thelike be carried against the surface of the annulus G by the wind, therewill be no tendency for the same to penetrate within the ventilator, buton the contrarv, the more powerful the air current K, the more effectivewill be the suction through the uptake B. Moreover, the narrowing of thedistance between the annuli F and G Patented Feb. 23, 1915.

and the base plate A occurring at the orifice of the suction funnel Cincreases the efficiency of the draft.

\Vhat I claim is: a

In a railway car roof ventilator a vertical uptake shaft, a supportingplate on said up take shaft, an annular suction funnel of sectional areadiminishing from its junction with the uptake shaft to its outlet, saidfunnel so curved that the direction of outflow is substantially parallelto that of infioW, a transparent covering plate, an annulus connectingthe circumference of the covering plate to the outer circumference ofthe suction funnel orifice such annulus inclined at an angle of about 45to the supporting plate, and an annulus connecting the outside of thesuction funnel at about its junction With the uptake to the innercircumference of the suction funnel orifice said FREDERICK HENRY ADDIS.

Witnesses:

HERBERT SEF'roN J ONES, LEONARD E. HAYNES.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

Washington, D. 0.

